diff options
| author | Jiri Slaby <jirislaby@gmail.com> | 2006-12-08 02:39:03 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-08 08:28:58 -0800 |
| commit | 42f6384fe4747f65dc27e8a5f96502204558203b (patch) | |
| tree | 2426f001057d213fa89b0c2b790ddb93e4faa707 /drivers/char/sx.c | |
| parent | 927a6f9dd0d0b5f70cb2e0799ce7a3844f43d42f (diff) | |
| download | lwn-42f6384fe4747f65dc27e8a5f96502204558203b.tar.gz lwn-42f6384fe4747f65dc27e8a5f96502204558203b.zip | |
[PATCH] Char: sx, lock boards struct
Fix race condition which may occurs when multiple cards are probed at the same
time. Add mutex to critical sections to avoid this situation.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/char/sx.c')
| -rw-r--r-- | drivers/char/sx.c | 37 |
1 files changed, 23 insertions, 14 deletions
diff --git a/drivers/char/sx.c b/drivers/char/sx.c index 50cd64262a13..42427f4d2ebd 100644 --- a/drivers/char/sx.c +++ b/drivers/char/sx.c @@ -298,6 +298,7 @@ static int sx_init_drivers(void); static struct tty_driver *sx_driver; +static DEFINE_MUTEX(sx_boards_lock); static struct sx_board boards[SX_NBOARDS]; static struct sx_port *sx_ports; static int sx_initialized; @@ -1980,7 +1981,6 @@ static int sx_init_board (struct sx_board *board) } if (chans) { - /* board->flags |= SX_BOARD_PRESENT; */ if(board->irq > 0) { /* fixed irq, probably PCI */ if(sx_irqmask & (1 << board->irq)) { /* may we use this irq? */ @@ -2115,8 +2115,6 @@ static int __devinit probe_sx (struct sx_board *board) return 0; sx_dprintk (SX_DEBUG_INIT, "reset the board...\n"); - board->flags |= SX_BOARD_PRESENT; - func_exit(); return 1; } @@ -2211,8 +2209,6 @@ static int __devinit probe_si (struct sx_board *board) return 0; sx_dprintk (SX_DEBUG_INIT, "reset the board...\n"); - board->flags |= SX_BOARD_PRESENT; - func_exit(); return 1; } @@ -2396,10 +2392,15 @@ static int __devinit sx_eisa_probe(struct device *dev) unsigned int i; int retval = -EIO; + mutex_lock(&sx_boards_lock); i = sx_find_free_board(); - - if (i == SX_NBOARDS) + if (i == SX_NBOARDS) { + mutex_unlock(&sx_boards_lock); goto err; + } + board = &boards[i]; + board->flags |= SX_BOARD_PRESENT; + mutex_unlock(&sx_boards_lock); dev_info(dev, "XIO : Signature found in EISA slot %lu, " "Product %d Rev %d (REPORT THIS TO LKLM)\n", @@ -2407,7 +2408,6 @@ static int __devinit sx_eisa_probe(struct device *dev) inb(eisa_slot + EISA_VENDOR_ID_OFFSET + 2), inb(eisa_slot + EISA_VENDOR_ID_OFFSET + 3)); - board = &boards[i]; board->eisa_base = eisa_slot; board->flags &= ~SX_BOARD_TYPE; board->flags |= SI_EISA_BOARD; @@ -2430,6 +2430,7 @@ static int __devinit sx_eisa_probe(struct device *dev) return 0; err_unmap: iounmap(board->base); + board->flags &= ~SX_BOARD_PRESENT; err: return retval; } @@ -2498,16 +2499,19 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev, unsigned int i; int retval = -EIO; + mutex_lock(&sx_boards_lock); i = sx_find_free_board(); - - if (i == SX_NBOARDS) + if (i == SX_NBOARDS) { + mutex_unlock(&sx_boards_lock); goto err; + } + board = &boards[i]; + board->flags |= SX_BOARD_PRESENT; + mutex_unlock(&sx_boards_lock); retval = pci_enable_device(pdev); if (retval) - goto err; - - board = &boards[i]; + goto err_flag; board->flags &= ~SX_BOARD_TYPE; board->flags |= (pdev->subsystem_vendor == 0x200) ? SX_PCI_BOARD : @@ -2522,7 +2526,7 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev, board->base = ioremap(board->hw_base, WINDOW_LEN (board)); if (!board->base) { dev_err(&pdev->dev, "ioremap failed\n"); - goto err; + goto err_flag; } /* Most of the stuff on the CF board is offset by 0x18000 .... */ @@ -2546,6 +2550,8 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev, return 0; err_unmap: iounmap(board->base2); +err_flag: + board->flags &= ~SX_BOARD_PRESENT; err: return retval; } @@ -2611,6 +2617,7 @@ static int __init sx_init(void) board->irq = sx_irqmask?-1:0; if (probe_sx (board)) { + board->flags |= SX_BOARD_PRESENT; found++; } else { iounmap(board->base); @@ -2627,6 +2634,7 @@ static int __init sx_init(void) board->irq = sx_irqmask ?-1:0; if (probe_si (board)) { + board->flags |= SX_BOARD_PRESENT; found++; } else { iounmap (board->base); @@ -2642,6 +2650,7 @@ static int __init sx_init(void) board->irq = sx_irqmask ?-1:0; if (probe_si (board)) { + board->flags |= SX_BOARD_PRESENT; found++; } else { iounmap (board->base); |